[PDCL2(NH2(CH2)(12)CH3)(2)] SUPPORTED ON GAMMA-AL2O3 AS CATALYST FOR SELECTIVE HYDROGENATION

The [PdCl2(NH2(CH2)(12)CH3)(2)] complex supported on gamma-Al2O3 has p roved to be a considerably more active, selective and sulfur-resistant catalyst in the selective hydrogenation of styrene to ethylbenzene th an a traditional catalyst obtained from acid solutions of PdCl2, and e ven than the same complex unsupported. The active species is the compl ex itself and it is stable under the reaction conditions. Hydrogen tre atments above 353 K destroy the complex, at least partially, leading t o a less active and sulfur resistant catalyst. The higher sulfur resis tance, when compared to a conventional Pd/Al2O3 catalyst, can be attri buted to electronic and geometrical effects.